TABLE 1.

Mutations in ASLV-A TM that reduce sensitivity to an HR2 peptide

Mutation	TM location	R99 IC50 (μM)	Log IC50a	IC50 vs. WT	No. of times isolatedb	293T infectivityc
None (WT)	N/A	0.031	−7.51 ± 0.04	1.0	N/A	<3 × 10−5
T2I	N terminus	2.2	−5.66 ± 0.10	71	1	<3 × 10−5
S3L	N terminus	0.25	−6.60 ± 0.06	8.0	2	<3 × 10−5
D11N	N terminus	>50	>−4.3	>1,500	3	<3 × 10−5
D11E	N terminus	0.12	−6.91 ± 0.05	4.0	1	<3 × 10−5
E12K	N terminus	0.085	−7.07 ± 0.08	2.8	1	<3 × 10−5
A44V	HR1	0.090	−7.05 ± 0.10	2.9	1	2.2 × 10−4
V48D	HR1	7.9	−5.10 ± 0.14	260	2	1.1 × 10−1
K49E	HR1	0.54	−6.27 ± 0.25	18	1	<3 × 10−5
A51V	HR1	0.31	−6.51 ± 0.05	10	1	1.2 × 10−4
L53F	HR1	0.099	−7.00 ± 0.06	3.2	1	<3 × 10−5
G59R	HR1	0.12	−6.91 ± 0.02	4.0	4	<3 × 10−5
L62A	HR1	0.22	−6.65 ± 0.08	7.2	0d	2.0 × 10−2
V31I D60N	FP/HR1	0.22	−6.66 ± 0.10	7.0	1	<3 × 10−5

^aLog [R99] ± standard error.

^bNumber of independent populations from which this mutation was identified.

^cInfectious titer on mammalian 293T cells relative to titer on avian QT6 cells.

^dL62A is an engineered substitution.